Question 454Steam Plants - Assistant Engineer

The correct answer is A) positive displacement rotary pumps. Positive displacement rotary pumps are commonly used for fuel oil service on vessels because they are well-suited for transferring and circulating low-viscosity fluids like fuel oil. These pumps operate by trapping a fixed volume of fluid and forcing it through the discharge line, making them reliable and efficient for fuel oil applications. The other options are not typically used for fuel oil service. Nonvented plunger pumps (B) are more commonly used for higher-pressure applications, two-stage centrifugal pumps (C) are better suited for water handling, and explosion proof gear pumps (D) are not the standard choice for typical fuel oil service.